Seed starting 2014 Zone 5 b

I tried some new things this year. Only 2 days ago I just put in about an inch +/- potting soil and randomly sprinkled Heirloom Green sprouting broccoli seeds around the top. I used the see thru cover dome of a store bought cake. And placed aluminum foil on the top. Set it on a shelf away from the sunny window. And look at this growth.   

This container has failed 2 times. I tried pepper seed a few weeks ago. And lettuces a week ago. I looked closer to see it has a small vent for the hot food to release steam. So Today I put a plastic bag over it and will let it sit. To see if any thing happens. 

The cups in the window are doing great! I saved seed from the best watermelon we have had in years. And some tomatoes that were awesome. Name of seed is unknown. We bought them from local farms.